unusual graph-please help (2 Viewers)

jet · May 16, 2010

hscishard said:
Help!
Differentiate e^k/x

I stand by frenzal's point.

$\frac{d}{dx}\left (e^\frac{k}{x}\right ) = ke^\frac{k}{x} \frac{d}{dx}\left (\frac{1}{x} \right ) \\ = -\frac{ke^{\frac{k}{x}}}{x^2}$

nikkifc · May 16, 2010

jetblack2007 said:
$\frac{d}{dx}\left (\frac{e^k}{x}\right ) = e^{k}\frac{d}{dx}\left (\frac{1}{x}\right ) \text{ since } k \text{ constant} \\ = \frac{-e^{k}}{x^2}$

Well usually in the HSC they wouldn't that type of question. That expression that the person posted in order to be a smartass would most likely be $e^{k/x}$ in an actual HSC exam.

Also, I don't think he really needed help. He was just being a smartass, as I've stated.

frenzal_dude · May 16, 2010

nikkifc said:
Yeah but we know what the OP means... although yes, you should technically do it.

But in all seriousness, the frenzal guy should focus more on getting his mathematics up to scratch, rather than worrying about crossing his t's and curving his l's etc... they're very minor points...

minor point? I think it's a major point since without using the brackets you get 2 totally different expressions! In the exam I doubt the marker is going to think 'oh I know what the student meant', I'm pretty sure the student would get 0 for writing the expression without brackets.

hscishard · May 16, 2010

nikkifc said:
You obviously did get my point. My point was that you were being a pot calling the kettle black. If you were so perfect and so on, then you would've defined everything in your post, but you didn't so it shows something about you

The point was to make a question that's imperfect, similar to the question the OP made. That idiom doesn't fit in, does it now?

unusual graph-please help (2 Viewers)

jet

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nikkifc

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frenzal_dude

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hscishard

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